Re: [PATCH 0/3] drivers: expand usage of request_firmware_direct()

From: Takashi Iwai
Date: Thu Jun 26 2014 - 12:18:14 EST


At Tue, 24 Jun 2014 15:39:40 -0700,
Luis R. Rodriguez wrote:
>
> From: "Luis R. Rodriguez" <mcgrof@xxxxxxxx>
>
> Takashi added request_firmware_direct() via bba3a87e9 through v3.14-rc1
> which avoids the unnecessary delay introduced by using the udev firmware
> loader in case the first try failed when loading we know loading "firmware"
> is optional. The first use case was for microcode update but if drivers are
> using it for optional configuration updates, custom EEPROMs, and other
> junk other than firmware that should apply as well as good use cases,
> specially if the driver already had a first phase in which it loaded
> the first required firmware. While reviewing one driver I figured it'd
> be best to try to give formalizing a check with SmPL. This isn't perfect
> it had 1 false possitive drivers/fmc/fmc-fakedev.c on the entire kernel
> run but my hope is this can be extended a bit more to build more
> confidence, and then perhaps stuff it as a coccicheck.
>
> I suppose this will not be required once and if we remove
> CONFIG_FW_LOADER_USER_HELPER. Is that ever going away for good? I know
> there was a recent attempt to remove the udev loader support but
> it was unclear if the special alternative helper support would be
> removed upstream from the kernel.

Actually a few weeks ago I sent a patch to make request_firmware()
with usermode helper explicitly to be used by some drivers (like
dell-rbu). I hope Greg took it for 3.17. Once when this patch is in,
distros can turn off the usermode helper fallback gracefully, so no
ugly timeout issue shouldn't happen.


Takashi
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/